5 PhNHNH 2 ] formed during the course of reaction has been found to be 1:1 using the mole ratio method. The evaluated values of activation parameters for the catalyzed reaction are E a = 53.85 kJ mol −1 , H = = 51.33 kJ mol −1 , and S = = −134.63 J K −1 mol −1 , which suggest an interchange dissociative mechanism. A most plausible mechanistic scheme has been proposed based on the experimental observations.